I've got a few fans that need venting to the outside of the house, which will need vents on the external walls. The house is BAL29 rated, and the Standards say:
Vents and weepholes in external walls shall be screened with a mesh with a maximum aperture of 2mm, made of corrosion resistant steel, bronze or aluminium, except where they are less than 3mm.
Initially I thought that meant any vent needed to be made of metal, such as this: http://www.fansdirect.com.au/buy-fans-o ... ed-damper/. However, a gravity vent is fully closed unless operational, which wouldn't happen during a fire. So would this suffice: http://www.universalfans.com/vents-gril ... 1_1001260/?
The important things here are:
- -- not all the fans I'm using will be able to open a metal gravity vent (not enough pressure)
-- the dryer vent can't screened, or will clog up
Anyone with experience? This vaguery isn't particularly helpful...